2007 Honda Fit Real World Fuel Efficiency

Some call this Fuel Economy or Gas Mileage

Jump to a spreadsheet where you can determine how much
you're not saving by driving farther for cheaper gas.

This page details our record of fuel use for this car. We really
like the Fit. You can carry eight foot 2x6 lumber in the car! We are
hoping to get a roof rack for a canoe but haven't yet decided whether
to get the clamp on style, which many people recommend against,
or the through the roof style which leaves small permanent anchor points
on the roof.

The official efficiency ratings (l/100 km) for the 2007 Honda Fit are:
City Highway
7.3 5.8

We received an initial payout of $400 (called the Climate Action
Dividend) for our family of four and our income tax has also been
reduced.

The income tax reduction is not included here but obviously is contributing
to further benefits for us. In general people seem to have very little
understanding of how this excellent programme works. I hope a few numbers
from a real world example will help people understand. Only those who burn
a lot of fuel are being punished by the tax and for them it is great
incentive to reduce their fuel use (and carbon emissions!).

A further caveat in this analysis is that I have not included the fuel oil
we had to buy for the (1970s era) oil burning furnace that was installed in
our house when we bought it. We only spent one winter and a fall with that
furnace before we managed to arrange to remove it and replace it with an
electric air source heat pump. I have not included the carbon tax that we
paid on the fuel oil but it was probably about $20 or so. I don't have
good records of the fuel oil we bought ... on the other hand it was partially
(5% apparently) "bio" sourced oil so that part was
carbon-neutral.

With regard to the maintenance, we have done what the car has
told us to do by way of the dashboard maintenance codes. Insurance
on a modest car that is still reasonably new is about $1000 per year
here in BC for drivers with the maximum discount of about 40%.
Obviously, the per kilometre purchase cost will continue to fall and the
other costs will rise (somewhat).

I thought it might be appropriate to add a bit more information about
how I typically commute to and from work. For the past eleven years or so I
have used three different bicycles to commute. The commute is about five
kilometres each way. I ride rain or shine and even in snow (but ice is bad
news -- when icy I have walked or run or driven the car). Luckily ice
and snow are rare here in Greater Victoria. Eleven years of
commuting this way amounts to about 27 500 km by bicycle. Given
that my car produces 0.16 kg/km of CO2, using my bike
instead has prevented the emission of about 4400 kg of
carbon dioxide. I've also saved about $2200 on gasoline. If I
didn't have the car at all I could estimate how much money I saved
by bicycle commuting by using the per kilometre operating cost (shown
in the table above). Using 34 cents per kilometre amounts to ∼ $10 000 that
I wouldn't have had to spend on car ownership over the past ten years.

Bicycles certainly have some emissions cost associated
with their production and delivery but that's much less than similar
costs for a car. I would have only used two bicycles over this time but
one of mine was stolen and had to be replaced. Some people (many?) go through
a similiar changeover in new cars over ten years. Yes, I had a different car
for the first part of the last decade, but it was very similar in efficiency
(old, broken page
here).

Have you ever thought about the relationship between your car's
mass and its fuel efficiency?
Rhett Allain has.

What About Electric Cars?

[2015-11-16] Cradle to Grave
costs of Electric cars from the Union of Concerned Scientists.
"By the end of their lives, gas-powered cars spew out almost twice as much global warming pollution than the equivalent electric car. Disposing of both types of vehicles (excluding reusing or recycling their batteries) produces less than a ton each."

[2015-03-01 This section will need updating soon. It is getting increasingly out of date].

The idea that electric cars are somehow automatically better than those
powered by internal combustion is wrong. Electric cars have manufacturing
costs (in terms of carbon emissions) that must be taken into account.
Electricity production has similar, more obvious, carbon costs. Many people
have been looking into this question and it's not settled yet.
In a
recent article about the Tesla Model S you can read about some of the
issues such as battery production and generation techonlogy used for the electric grid.
It seems to me that electric cars are the future. There are still problems to
resolve but as the proportion of energy from renewable sources increases in the
electric grid, as battery technology improves, as the rest of our economies move
away from carbon emitting energy sources, the electric car will become increasingly
the only way that cars are manufactured. In the meantime it looks like the most
fuel efficient carbon fueled vehicles are comparable to the current models of
electric vehicles. In all cases it's best to use human power as much as possible
to get around.

Here's
another discussion of electric vehicles. The question in this case
is what is the cost and efficiency of converting the entire USA fleet (of cars) to
electric drive? The conclusion is that it would be an expensive way to reduce
overall CO2 emissions.

[2015-03-17 New] Download a spreadsheet to see how much you will save
by driving farther for less expensive fuel. Hint: not very much. Yes,
fuel costs 8.1 cents per km for my car. See below for more details.
If you really do this right you need to allow for the real cost per
kilometre which in my case is 34 cents/kilometre.

The carbon I'm emitting by burning fossil fuels has a large relative impact on
the climate system because some of it will stick around for many thousands of years.
Using David Archer's
SLUGULATOR model you can work
out the long term effect of a slug of carbon in the environment. Because some of any initial
slug remains in the system for many thousands of years the long-term effect is very large.
How large? Similar to five seconds worth of solar energy at the top of the Earth's
atmopshere or the energy released through nuclear fission of 90 kg of Uranium-235.

Figures

Fuel Use Versus Distance Travelled

Colours indicate the order of the fill-ups. Red is most recent and
blue is oldest. The ROYGBIV rainbow order is followed
(approximately). The lines show the official efficiency ratings:
dashed is city travel and dotted is highway travel. Ideally we would
want to see all of the observations between or below these lines. The
red dash-dotted line is the best fit to the data assuming that the
line goes through the origin -- it must, you don't use any
fuel if you don't drive any distance. It seems pretty clear that if
we could isolate the observations related solely to city driving the
slope would be steeper (worse) than the official rating. Is this
related to driving style? The car is driven by two different
drivers. That variable is rolled up in the observations as well.

Distance Travelled

Fuel Efficiency as a function of date

Gasoline Price

Cumulative fuel consumption

Fuel consumption vs. Distance driven

When I heard about "GasPods" I didn't believe they could
really have a significant effect. Since belief that something happens
doesn't actually help you know it happens I bought a set and am doing
my own test of their efficacy.

[Update 2015-06-24 The simple statistical test I am doing now shows that the
means of the two pools of observations are most-likely not equal. I find this
surprising but there you have it. This simple case does seem to support the
claims of the GasPod designers.]